用polarity reversal造句子，“polarity reversal”造句

Magnetic minerals trapped inside ancient rocks have recorded hundreds of these so-called polarity reversals in the past500 million years.

This paper introduces the formation of magnetic field, polarity reversal, secular variation and the use of geomagnetic polarity reversal or susceptibility in stratigraphic study.

If a cell does get fully drained, though, it can go into a state known as polarity reversal, in which the surrounding good cells drive the bad one in reverse.